docs: def release(self, resource):
          """release(resource)
  
          Returns a resource to the pool. Most of the time you will want
          to use :meth:`transaction`, but if you use :meth:`acquire`,
          you must release the acquired resource back to the pool when
          finished. Failure to do so could result in deadlock.
  
          :param resource: Resource
          """
          with self.releaser:
              resource.claimed = False
              self.releaser.notify_all()